Advanced

These scopes provide the best performance but may require more skill to master and appreciate. They have exceptionally fine optics and mechanics. Some are easy to use but are but on the large or heavy side. Some are intended for specialized uses. These scopes will appeal to the more technically inclined. Referring to the manual is highly recommended.

For the dedicated visual observer or imager seeking a top-of-the-line instrument to advance their capabilities and enjoyment in the hobby, the Orion EON 130mm Triplet ED Apochromatic Refractor should be on your short list of candidates. This exquisite telescope features premium optical performance and a high-end fit and finish, but at a price that's thousands less than that of comparably sized apos from other manufacturers. From front to back, this is truly an awe-inspiring telescope.

At the front end, you'll find a three-element, air-spaced lens assembly of 130mm (5.1") aperture, with one element crafted from FPL-51 ED glass for superb color correction and sharpness. The 910mm focal length makes the EON 130mm Triplet a wonderfully versatile telescope for both deep-sky and solar system imaging or stargazing with plenty of image scale for smaller targets and a moderately fast f/7.0 focal ratio. All air-to-glass lens surfaces bear antireflection multi-coatings for superior light transmission. Contrast is equally rich thanks to blackened lens edges and two internal knife-edge baffles that prevent off-axis reflections of incoming light. The EON 130mm Triplet ED Refractor features an extendable dew shield that further ensures excellent contrast and helps inhibit dew formation on the lens.

At the back end of the EON 130mm Triplet ED, you'll find a heavy-duty 3" dual-speed Crayford focuser with precise 11:1 fine focus control. Astrophotographers will appreciate that the telescope's focuser can be rotated in two places, allowing camera framing to be set independently from positioning of the focus knobs at the desired orientation. The focuser features an Orion finder scope base for attachment of any Orion reflex sight or finder scope, if desired. The big focuser's 3" drawtube sports an engraved millimeter scale to aid in focus point repeatability, and features a focus-lock thumbscrew, both of which are especially useful for astrophotography. Both the 2" accessory collar on the focuser drawtube and the 1.25" adapter feature non-marring brass compression rings.

This is a telescope that is so beautiful you'll want to keep it displayed in your living room for all to admire when you're not using it under the stars, but when you are using the Orion EON 130mm Triplet ED Refractor - whether for visual or astrophotographic pursuits - you'll be mightily impressed.

Weighs 22.5 lbs.

Warranty

Limited Warranty against defects in materials or workmanship for one year from date of purchase. This warranty is for the benefit of the original retail purchaser only. For complete warranty details contact us at 800-676-1343.

User level

Level 1 Beginner - Suited for a wide range of uses, these telescopes are simple to operate and set up. Some initial assembly may be required. Very good optical and mechanical quality. Great for families, young people, and folks who don't want to mess with equipment but just want to take a look. Any of these scopes will show you countless lunar craters, Saturn's rings and a myriad of star clusters and nebulas! Referring to the manual is recommended.

Level 2 Intermediate - These scopes offer higher performance and more advanced features than Level 1: Beginner models. They typically take a bit longer to learn and need some set-up or adjustments. But anyone with the slightest technical bent will have no problem getting familiar with these models. Referring to the manual is recommended.

Level 3 Advanced - These scopes provide the best performance but may require more skill to master and appreciate. They have exceptionally fine optics and mechanics. Some are easy to use but are but on the large or heavy side. Some are intended for specialized uses. These scopes will appeal to the more technically inclined. Referring to the manual is highly recommended.

Level 4 Expert - Expert telescopes offer uncompromising optical and mechanical quality for the most demanding amateur astronomer. They may be technically involved or designed for specialized use, such as astrophotography or detailed deep sky observation. They carry a premium price, but are designed to provide the ultimate performance in the field. Referring to the manual is highly recommended.

Optical design

Reflector telescopes use a pair of large and small mirrors to direct incoming light to the eyepiece.
Refractor telescopes refract, or "bend" incoming light to a focus by means of an objective lens.
Cassegrain telescopes, such as Maksutov-Cassegrains, "fold" incoming light using two mirrors and a front "corrector" lens.

Optical diameter

For telescopes, the optical diameter (also known as aperture) is the size of a telescope's main light-collecting lens or primary mirror, measured in millimeters or inches. Telescopes with larger optical diameters collect more light, which leads to an increase in brightness and image resolution compared to smaller instruments.

For binoculars, the optical diameter (also known as objective lens diameter) is the size of each of the front-facing objective lenses of a binocular measured in millimeters. Binoculars with larger objective lenses collect more light, which increases image resolution and brightness. Binoculars with larger objective lenses are recommended for low light situations, and binoculars with at least 50mm or larger objective lenses are recommended for pleasing astronomical observations at night.

Focal length

The distance from the center of a curved mirror or lens at which parallel light rays converge to a single point. The focal length is an inherent specification of a mirror or lens and is one of the factors in determining resultant magnification for a telescope (along with the focal length of the eyepiece being used).

Focal ratio

The focal ratio of an optical system is the ratio of a telescope's focal length to its aperture. Short focal ratios (f/5, f/4.5) produce wide fields of view and small image scales, while long focal lengths produce narrower fields of views and larger image scales.

Coatings

Binocular lenses and prisms are often coated with anti-reflective material to minimize light loss as light travels through the multiple optical surfaces of a typical binocular. Coatings help maximize the amount of light transmitted through each glass surface of a binocular, so as much light as possible reaches the observer's eyes to provide a bright and sharp image.

Good lenses are at least "fully coated," with a single layer of magnesium fluoride coating applied to each air-to-glass lens surface. Multiple layers of coatings are even more effective; the term "multi-coated" means one or more air-to-glass lens surface has multiple coatings. "Fully multi-coated" optics are even better, meaning all lens surfaces have multiple layers of anti-reflective coatings applied for maximum light transmission and optimal image quality.

Optics type

Newtonian reflectors will have either a spherical shaped mirror, which is less expensive to produce, or a higher quality parabola, which does not result in spherical aberration. Cassegrain telescopes routinely use spheres in addition to other lenses in the optical path to correct for residual spherical aberration.
Refractors use a series of lenses to provide a clear image. Designs range from a standard air-spaced doublet (two lenses in a row) to exotic designs such as oil-spaced triplets and 4-element multi group lenses.

Glass material

Refractors use glass lenses to focus the light, and the glass material plays an important role in the quality of the resulting image. Standard achromatic refractors routinely use Crown and Flint for the two elements, but more expensive apochromatic refractors can use ED (extra low dispersion) glass for one or more of the lenses. Reflector mirrors are made from glass with different levels of thermal expansion. Standard mirrors are made from material such as Soda-Lime Plate glass and BK-7 glass. Glass with Pyrex or other low thermal expansion material will not change shape as dramatically during the cool-down period, resulting in more stable images during this period.

Resolving power

The theoretical resolving power of a telescope can be calculated with the following formula: Resolving power (in arc seconds) = 4.56 divided by aperture of telescope (in inches). In metric units, this is: Resolving power (in arc seconds) = 116 divided by aperture of telescope (in millimeters). Note that the formula is independent of the telescope type or model, and is based only upon the aperture of the telescope. So the larger the telescope's aperture, the more it is capable of resolving. This is important to keep in mind when observing astronomical objects which require high resolution for best viewing, such as planets and double stars. However, it is usually atmospheric seeing conditions (not the telescope) which limits the actual resolving power on a given night; rarely is resolution less than one arc-second possible from even the best viewing locations on Earth.

Lowest useful magnification

Lowest useful magnification is the power at which the exit pupil becomes 7mm in diameter. Powers below this can still be reached with the telescope to give wider fields of view, but the image no longer becomes brighter at a lower power. This is due to the fact that the exit pupil of the telescope (the beam of light exiting the eyepiece) is now larger than the average person's dark adapted pupil, and no more light can fit into the eye.

Highest useful magnification

The highest practical limit is different from the often used "highest theoretical magnification" specification. The "theoretical" limit generally is 50x the aperture of the scope in inches (2x the aperture in mm). So for example, an 80mm refractor is capable of 160x, and a 10" telescope is theoretically capable of 500x magnification.
But after approximately 300x, theory breaks down and real world problems take over. The atmosphere above us is constantly in motion, and it will distort the image seen through the telescope. This effect may not be noticeable at lower powers, but at higher powers the atmosphere will dramatically blur the object, reducing the quality of the image. On a good night (a night where the air above is steady and the stars aren't twinkling), the practical upper limit of a large telescope is 300x, even thought the theoretical limit may be much higher. This doesn't mean the scope will never be able to reach those higher "theoretical" powers - there will be that rare night where the atmosphere is perfectly still and the scope can be pushed past it's practical limit, but those nights will be few and far between.

Astro-imaging capability

The astro-photographic capability of the telescope is based on the style, stability, and accuracy of the mount and tripod. Telescopes on either very lightweight mounts or non tracking mounts (such as Dobsonians) are capable of only very short exposures such as lunar photographs. If a motor drive is attached to an equatorial mount, even a small lightweight mount is capable of capturing some planetary detail. Larger EQ mounts that utilize very precise tracking and excellent stability are capable of longer exposure deep-sky photography.

Warranty

This warranty gives you specific legal rights. It is not intended to remove or restrict your other legal rights under applicable local consumer law; your state or national statutory consumer rights governing the sale of consumer goods remain fully applicable.

Orders received by 1pm Eastern Time for in-stock items ship the same business day. Orders received after 1pm will ship the next business day. When an item is not in-stock we will ship it as soon as it becomes available. Typically in-stock items will ship first and backordered items will follow as soon as they are available. You have the option in check out to request that your order ship complete, if you'd prefer.

Attach two different aiming devices to your telescope quickly and easily with the Orion Dual Finder Scope Mounting Bracket. Use any combination of finder scope, reflex sight, green laser pointer bracket, mini guide scope, without having to use tools.

Are you having trouble seeing the crosshairs in your finder at night? By using an adjustable-intensity red LED, the Orion 9x50 Illuminated Finder Scope with Bracket makes it easy. Features multi-coated achromatic optics and adjustable focus

The Orion EZ Finder Deluxe II Telescope Reflex Sight gives you 4 different patterns to choose from to make aiming your telescope easy. Features both red and green LEDs for easy aiming at night or during the day, and 5 different brightness levels.

Slightly higher power than the 32mm, the 26mm Orion Q70 Wide-Field Eyepiece still gives you the super-wide 70-deg field of view, great for a new perspective on your favorite objects. The multi-coated lenses provide clear, high contrast images.

If you're looking for a heavy duty GoTo mount for all your observing or astrophotography needs, the Orion Atlas EQ-G computerized GoTo telescope mount is perfect. It supports up to 40lbs and finds over 42,900 celestial objects with pushbutton ease.

The Dew Zapper Pro is an advanced telescope dew prevention system that powers up to 4 dew-eliminating heating bands for all your opticals. Each heating band has a separate temperature control knob and each band (sold separately) is very efficient.

The Orion StarShoot G3 Color imaging camera provides cutting-edge astrophotography technology at an unbelievably low price. If you've been thinking of exploring the rewarding realm of astrophotography, the StarShoot G3 Color imager is made for you!

This heating band works with the Dew Zapper Pro control module (sold separately) and fits 150mm (6") - 203mm (8") telescopes. It prevents dew from forming on your optics allowing you to view and image longer. Includes a 6' cable.

This affordable kit is ideal for anyone interested in exploring deep-sky objects. Includes three 2" DeepView eyepieces - 42mm, 38mm, and 28mm focal lengths, a 2" Barlow lens, and a 2" SkyGlow Broadband Filter, and a large pluck-foam accessory case.

The Orion Wide Universal Dovetail Plate allows you more versatility with your wide-saddled mount. It has multiple holes along the length so you can mount all manner of accessories, including rings and cameras with a tripod socket, where you need it.

If you are an avid astronomer you know that you should always use red light instead of white to help protet your night vision. The Orion RedBeam II LED Flashlight has adjustable brightness which lets you observe without ruining your night vision.

At Orion, we are committed to sharing our knowledge and passion for astronomy and astrophotography with the amateur astronomy community. Visit the Orion Community Center for in-depth information on telescopes, binoculars, and astrophotography. You can find astrophotography "how to" tips and share your best astronomy pictures here. Submit astronomy articles, events, and reviews, and even become a featured Orion customer!